Telephone systems must record details of telephone activity in order to appropriately bill customers for the services provided. Errors in call detail recording (or "CDR") can result in significant revenue loss to the telephone service provider. Such errors can be caused by call provisioning errors, errors in the transmission of billing information between telephone systems, errors in billing number screening databases, and hardware and software errors.
CDR errors are usually discovered in down-stream billing systems long after they have occurred. Earlier detection can lead to correction of the problem and minimization of the revenue loss.